Portable filter



Nov. 20, 1945; s. FARRELL PORTABLE FILTER Filed July 21, 1943 3 Sheets-Sheet 1 I38 44 42 2 3.$' I5 I 4a /a H w m 7 ,4, '55 5 47 27 5 ll x /5 78 J37 J7 80 r31 7 I LAWRENCE S. FARRELL INVENTOR.

BY H/f/ ATTORNEY Nov. 20, 1945. s. FARRELL 2,389,189-

PORTABLE FILTER Filed July 21, 1945 :5 Sheets-Sheet 3 /4/ A LAWRENCE S. FARRELL i INVENTOR. 1 I33 K 15 WW W6 W ATTORNEY] Patented Nov. 20; 1945 roar FILTER Lawrence S. Farrell, Fort Wayne, Ind., assignor to S. F. Bowser & Company,

Incorporated, Fort Wayne, Ind, a corporation of Indiana Application July 21, 1943, Serial No. 495,788

3 Claims. 210-40) This invention relates to a portable, powder type filter. More specifically, it relates to a filter which utilizes a coating of filter aid material upon a screen for removing solid and semi-solid material from a liquid, which has means for adding powder continuously to the screen to maintain a porous cake and which has means for adding a disinfecting material to the liquid to render it safe for drinking.

A great number of filters are disclosed in the prior art for filtering various liquids, Some filters utilize sand, gravel, diatomaceous earth, fullers earth and other media for accomplishing the filtration.

Furthermore, it has been found that even if a large, heavy filter is installed in the field, conditions do not always make it possible to distribute the pure water to the men who require it. In addition, destruction of the single unit leaves a great many men without a source of water supply.

Accordingly it is an important object of the invention to produce a unit which is small enough and light enough to enable a man to carry it.

It is another object of the invention to produce a unit which is efficient so as to reduce to a minimum the amount of supplies needed to operate the device.

Still another object of the invention is to provide a unit which has built into it all of the equipment required to enable an operator to convert any reasonable source of water into a safe drinking water.

Yet another object of the invention is to provide a filter which can be operated with a minimum of personnel.

Itis still another object of the invention to provide a, unit which will have a relatively long cycle of operation.

Yet another object of the invention is to provide a filter having means for adding disinfecting materials to the water.

Another object of the invention is to provide a filter and means for continuously'adding filter aid to the screen.' A

Still another object of the invention is to provide a filter which is simple and rugged.

These and other objects will become apparent from a study of the specification and the drawings which are attached thereto and which form a part thereof, and in which:

Figure 1 is a side elevation with parts broken away showing the pump, filter and a feed pot.

Figure 2 is a rear elevation with parts broken away to show the construction of the feed pots.

Figure 3 is a top view with parts broken away to show the orifice which effects feeding of material from the feed pots.

Figure 4 is a sectional view of the feed pot control valve.

Referring now to Figures 1 and 3, the numeral i represents a number of tubular members which are welded together to form a frame. A plurality of supporting lugs 3 are welded on the frame and support by means of screws 5 and a head casting i.

Th head i is recessed at 9 to receive a pump body II and the body is provided with an end cap l3. Stud bolts l5 hold the cap and pump body in place on the head.

A bearing I! is inserted in a recess IS in head I and a bearing 2| is set in a boss 23 in the cap l3. A shaft 25 is iournalled inthe'se bearings and carries a rotor 21 within the pump body and a handle 29 on its outer end. The hub of the handle is notched at 3| to receive the key 33 which passes through the shaft. The handle is thus removable.

A plurality of blades 85 lie in slots in the rotor 21 and engage at their outer ends the bore 31 in the body H. An inlet connection 89 enters the body and an outlet port ti is formed in the cap it. A three-way valve 8G is connected to port 39. A conduit 52- 54 is cored in the cap and a transverse wall 43' in the conduit is provided with an orifice A5. A transparent tube ll connects the conduit with a cored passage 49 in the head i which leads to a downwardly extending tube 5 l.

A circular recess 53 is formed on the lower side of the head to receive a gasket 55 and a ring 51 which is fixed to the upper edge of a tank 59. This tank has a bottom fit'which is perforated to permit the passage of the tube 5i through it. A plug 6| is provided at the'bottom of the filter for draining the tank 58 or for filling it with sand in the event regular filter aid is not available. A reinforcement 83 is fixed to the bottom of the tank and the end of the pipe 5| is threaded to receive an acorn nut 85. The lat.- ter carries a gasket 61 which bears against the reinforcement to seal the joint. The nut is provided with projections 69 which enable the operator to compress the gaskets 55 and 61 to seal the joints.

The tube 5| is provided with openings 1| just above the bottom of the tank so that liquid issuing therefrom will stir up any powder which may drop down into the tank. The interior of mesh outer screens. 18, 8I and a coarse inner screen 88, is soldered in place in the recess 18, The lower end of the screen is closed by filling in the space between the ends of the outer screens 'with solder. I

A plate 81 is welded to the frame I and carries two circular, flanged caps 88, 8I. A feed pot 88 having an open but flanged top is adapted to enter cap 88 and bear against a gasket 85. A-

stirrup 81 is supported by nuts 88 on the plate 81 and carries an upwardly directed screw I8I which is disposed substantially coaxially under the feed pot. The latter has an axially directed cylindrical boss I88 which is received in a recess I 85in a'nut I81 which is mounted on the screw I8I.

The feed pot I88 is constructed and supported in a manner similar to pot 88.

A tube III is connected at one end to the conduit 42 which is between the pump discharge port H and the orifice 45 and is connected at the other end to a T fitting I I3.

From one branch of the T a pipe II runs to a needle valve I I1 and thence substantially along the axis of the feed pot 88 and terminates near the bottom thereof substantially at the level where the boss I88 begins. Two laterally directed orifices H8 and I2I and a downwardly directed orifice I28 are formed in the pipe.

The second branch of the T is connected to a pipe I25 which has a needle valve I21 and lets I28, I8I and I88.

A discharge tube I85 which is plugged at its lower end is provided with ports I81 adjacent the top of pot 83. This tube is connected by a threeway selector valve I88 with conduit 44 at a Point between orifice 45 and the transparent tube 41.

A similar discharge tube I'4I enters the pot I88, is provided with ports I48 and connects with valve I88.

Fixed to the upright frame members and to the tank, as shown in Figures 1 and 2, are clips I45, I41 and I48. A waterproof bag I5I carries rods I58 and I55 on the two longitudinal edges and the rod I58 is held in clips I45 and I41 while rod I55 is held by clip I48.

A suction hose I51 is connected to one inlet port of the three-way valve 48 and the open end of the hose is disposed in the bag. A second suction hose I58 is attached at one end to the other inlet port of valve 48 andat the other end to a screen I6I which may be of any suitable con-- struction. A check valve I55 is mounted in the screen and serves to prevent any back fiow of liquid from the filter toward the screen which would tend to dislodge the filter cake from the screens.

Connected to the conduit 44 is a relief valve I88 which may be of any desired type. An adiustable type is preferred so that the maximum.pressure on the filter may be varied if desired.

Operation v If we assume that it is desired to use the filte 'as a powder filter, the feed pot 88 is filled with a disinfectant solution such as calcium hypochlo- A cylindrical screen which comprises two fine rite or sodium hypochlorite, or a powdered or fibrous material treated to give it oligodynamic properties, and clamped in place in the cap by means of th nut I81. There is of course noth- 5 ing to prevent either or both pots from being used for that purpose. However, if the source or water to be used is very muddy the other feed pot is filled with a mixtureof water and filter aid such as diatomaceous earth, activated carbon or other suitable material.

The bag III is partially filled with filter aid (about 3 ounces) and the discharge hose 82 is arranged in discharge into the bag I5 I The valve 48 is then set to draw water through the suction hose I58 and screen I5I which must be connected with the valve. Preferably, the hose I58 should be laid on a steady down grade to the screen so that no air pockets will form in it.

When this is accomplished, the selector valve I88 is set to draw from pot 88 and the needle valve H1 is opened about one turn. Thereafter, the crank handle 28 is turned and water will be drawn up into the pump and will be discharged Into the filter through conduit 42, orifice 45, conduit 44, tube 41, conduit 48, tube 5I and openings H. The, filter will fill and water will Pass through the'screens 18, 8I and 88, ducts 15, channel 11, outlet 18 and by way of hose 82 to the bag I 5|.

When the bag is about twosthirds full, pumping is stopped and valve 48 is turned to draw the mixtureof water and filter aid from the bag. This material is circulated until the water passing through the transparent tube 41 is crystal clear.

While the filter is being charged and precoated. the pressure in conduit 42 will be greater than that in 44 because of the orifice 45. This causes.

As soon as the precoat is established and the water is clear, the valve 48 is turned to cut oil the hose I51'and connect the raw water suction hose I58. This is preferably done without stopping the pump, because otherwise there is danger of the precoat dropping from the screen. The discharge hose 82 is then transferred to the pure water storage container such as a canteen and the efliuent is safe drinking water.

55 The needle valve H1 is regulated to give the proper residual chlorine (if'chlorine is used as the disinfectant). This chlorine residual is determined by the Orthotolodine test. Since the water entering the feed pot gradually dilutes the solution therein, it is necessary for an assistant operator to make the chlorine test at least every ten minutes and to regulate the valve II1 as it is shown to be required by the tests.

The valve shown in Figure 4 will permit either or both feed pots to be drawn from or may be set to close 011 both pots.

- In the position shown in this figure the port alignment is A-I4I, B-I and C--44 so that both pots will feed the filter.

70 If the valve is rotated degrees counterclockwise the port alignment is A-44,-B'I4I so that pot I88 will be connected but pot 88 will be cut off.

If the valve is rotated degrees from the 75 Figure 4 position the port alignment will be asearec B-fl, C-l35 and pct 93 will be connected while pot 19 will be cut off.

If the valve is rotated 270 degrees counterclockwise or 90 degrees clockwise, the port alignment will be Ai35, C-Hl and neither pot will be connected to the filter.

Assuming that the water is muddy, it is desirable to add a continuous supply of filter aid and a carbon mixture from feed pot I09 at the same time that the disinfectant is being added. This is done by adjusting the valve I21. The operator readily learns to judge the proper opening of the valve in relation to the turbidity of the water as observed in the transparent tube.

The addition of filter aid lengthens the filtration cycle because it maintains the cake porous. The end of the cycle is reached when water is discharged from the relief valve and this valve is preferably set to open when the pressure reaches about 20 p. s. i. 1

The construction of the orifices at the bottom of the tubes H5 and I25 is such that the incoming water will issue in jets which create a turbulence and keep the powder or other solids which might otherwise settle out, in suspension in the water.

To clean the filter it is necessary only to remove the nut 65 and drop the tank 59. The sludge may then be cleaned from the screens with a stick or a piece of metal and the tank can be washed or swabbed out. Cleaning of the pots is accomplished by loosening the nuts I01 and removng the pots from their associated caps and scraping and/or washing them.

It is obvious that various changes may be made in the form, structure and arrangement of parts without departing from the spirit of the invention. Accordingly, applicant does not desire to be limited to the specific embodiment disclosed herein primarily for purposes of illustration; but instead, he desires protection falling fairly within the scope of he appended claims.

What I claim to be new and desire to protect by Letters Patent of the United States is:

1. In a light weight portable liquid filtering apparatus, the combination of a tubular frame, a pump body mounted on said frame, a pump inlet, a pump discharge passage in said body, a

filtrate outlet, a double faced filter screen suspended from said body and having its interior being in the form of a hollow cylinder and having filtering surfaces on both inside and outside.

2. In a light weight portable liquid filtering apparatus, the combination of a tubular frame, a pump body mounted on said frame, a pump inlet, a pump discharge passage in said body, a filtrate outlet in said body, a double faced filter screen suspended from said body and having its interior connected and communicating with said filtrate outlet, 3, filter tank removably mounted upon said body, surrounding said screen and communi cating with said pump outlet, said filter screen being in the form of a hollow cylinder and having filtering surfaces on both inside and outside. and a plug in said tank adjacent the lower end of said screen and extending laterally beyond each of the filtering surfaces.

3. In a liquid filtering and disinfecting apparatus, the combination of a filter having a dual surfaced filtering element with a filtrate channel between said surfaces, pump having an inlet connected to a supply source, a conduit connecting said filter and pump and having a fiow restricting device therein, feed pots for disinfectant and filter aid, means connecting said pump with said pots and said feed pots with-the conduit and device to discharge disinfectant and filter aid from said feed pots into said filter, a container for precoating slurry, means for circulating said slurry through the pump and filter to establish a precoat on surfaces of said filtering element, a sight glass in said conduit for determining the precoating cycle, a raw liquid supply line, a means for connecting said pump inlet at will to either the supply line or said container.

LAWRENCE S. FARREIL. 

